an internal quantum number used in the classification of elementary particles. Particles which have very similar properties except for those associated with their charge are regarded as forms of the same fundamental particle with different components of the isospin in a certain direction in an imaginary space
Also called: isobaric spin, isotopic spin
isospin in American English
(ˈaɪsoʊˌspɪn; ˈaɪsəˌspɪn)
noun
Particle Physics
a quantum number used to distinguish the various states of electrical charge of a subatomic particle